<template>
  <div class="my-tab-bar">
  	<div v-for="(item,index) in arr" :key="index" 
    class="tab-item" @click="btnFn(index)" 
    :class="{current: curIndex===index}">
      <!-- 图标 
      动态绑定类名的另一种写法：:class="[类名1,类名2....]"
      -->
      <span class="iconfont" :class="[item.iconText]"></span>
      <!-- 文字 -->
      <span>{{ item.text }}</span>
    </div>
  </div>
</template>

<script>
export default {
  props: {
    arr: {
      type: Array,
      required: true,
      validator(arr){
        // 当validator函数返回true的时候表示校验通过，否则校验失败
        return arr.length>=2&&arr.length<=5; 
      }
    }
  },
  data(){
    return {
      curIndex: 0
    }
  },
  methods: {
    btnFn(index){
      // 保存点击按钮的下标值
      this.curIndex = index;
      // 1、子传父，把当前需要显示的组件对象名传递给父组件
      this.$emit("sendData", this.arr[index].componentName)
    }
  }
}
</script>

<style lang="less" scoped>
.my-tab-bar {
  position: fixed;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 50px;
  border-top: 1px solid #ccc;
  display: flex;
  justify-content: space-around;
  align-items: center;
  background-color: white;
  .tab-item {
    display: flex;
    flex-direction: column;
    align-items: center;
  }
}
    
.current {
  color: #1d7bff;
}
</style>